Tail light not working at all done connectors,fuse,

Try disconnecting both tail lights replace the fuse and see if it blows...if it don't connect one at a time and see what happens...also check you third brake light...

-Check power and ground at the bulb connector.
-If power present there but no ground then need to re done ground.
-If both line are good. then the bulb itself is bad.

Good luck

Mai

There is only one circuit. You have to trace the wire from the fuse to find the short. The wire runs to all of the parking and tail lamps as well as the instrument panel, thru the dimmer. If you find connectors along the way, disconnect them to find out if the short is beyond or behind the connector, using an ohmmeter.

Tail lights on a 7 pin connector is a brown wire and I would check at the plug and if you haven't done so then both the plug and connector wire ends should be soldered because sometimes they do not make a good connection with just a bare copper wire.

If both tail lights are not working it is likely to be a fuse or bad connection under the hood or a connector at the back see if you can trace the wires to a connector and see if it is dirlty or corroded.

Check your fuses. Dash lights and tail lights are on the same fuse. Check the fuses electrically, just looking at them is not enough. Replace any blown or damaged fuses with fuses of the same rating, NEVER use a fuse of a higher rating. If the fuse blows again, you have a short circuit to ground. Check all the front and tail lamps and their wiring and don't forget the trailer connector if you have one fitted..

ck rear tail light sockets for cracks broken wires. and terminals in connectors are not touching

I had this same symptom after I pulled a trailer that had light "issues". I tried wiggling the trailer light connector around until the trailer lights begin working. Next think I know they were not working again and now my left tail light was out. I thought it odd that is wasn't both lights out being on the same fuse, but checked wiring etc with no problems found. Mine turned out to be the "left tail light fuse" in the engine compartment fuse box. All of the parking and tail lights as independently fuse, You can tell which one it is by the guide on the fuse box lid. You will be looking for a 10 amp (red) fuse near the center of the fuse box.

rgant

An 89, that old enough that oxidation could be a problem.
I'd start by separating all the connectors you can get to, unfortunately there may be one over the gas tank. You can take a light and see if there is one by having someone pull and release the tail light wire as you look.
Thoroughly clean each end of the connector until you can see a little copper show. If it looks like there was grease on the connector, apply some dielectric grease before you reconnect the wires.